The appeal, which aired in February 2013 – five years after Mr Hall disappeared – included a picture of Mr Hall standing at the side with two men in the centre, one being a topless man with a goatee beard and shaved head.

Officers said they wanted to speak to the two men seen looking towards Mr Hall in the photograph, as they could be potential witnesses to his movements. They were thought to be British nationals.

Pictured: The last known sighting of Daniel and the men the police are trying to find. Submitted by Norfolk Police.

Detectives were encouraged by the appeal, which generated 25 calls to them and provided a number of names – but despite the new information, Mr Hall remained missing.

A spokesman for Norfolk Police has today issued a renewed appeal for information ahead of the 10th anniversary of his disappearance later this month.

The spokesman said: “We’ve completed all existing lines of enquiry and the investigation remains open. We would of course act on any new information received and encourage people who may know the whereabouts of Daniel Hall to come forward.”

Mr Hall had a history degree from Birmingham University but had been working in Norwich as a labourer before travelling to Thailand.